Water Temperature Controls
A water temperature control unit can be very useful when mixing chemistry or processing film. Film emulsions are sensitive to gross time and temperature changes. Isn't it always the case that just when you are processing your negatives, the person upstairs flushes the toilet and the temperature spikes? A panel regulates your temperature and keeps your water at a constant temperature, facilitating consistent processing. Traditionally, control panels are mounted on a wall over the sink where they can easily be reached. Some have a built-in flow meter, water filter and multiple filters.
Temperature is adjusted via a dial that controls a sweep hand on a gage. Some plumbing may be required to attach it to your main water supply. Generally, these connections are not difficult to make with the panels themselves usually accepting standard couplings.
In the absence of a water control panel, a good quality photographic thermometer is desirable. If you want good negatives and prints, knowing the correct temperature of your chemistry is mandatory since most chemistry requires a specific temperature to operate at peak performance.
Stainless steel stem thermometers with large dials are easier to read than smaller glass models. The small glass ones are good for tray processing. You can also buy a Flo-Temp, which is an adapter that fits on to the spigot of a faucet and has a slot for a thermometer.
As you manipulate the hot and cold valves, you will see the thermometer go up and down accordingly.